Kuonji Mermaid and Knight who have taken over the traces of a large company due to the sudden accidental death of their parents. The mermaid sells his body to get loans and aid to keep the company alive. The knight, who has exceeded the limits of his sister’s appearance, devoting himself to a man day after day, asks the mermaid to kill her. However, the mermaid scolds such a knight for regaining the same sadness as he lost his parents, and reminds him that he will die as much as the knight dies. The knight recovers from the words of his sister, who should have been more painful than himself, and the two who have a mutual heart are connected physically.